Optical imaging lens

ABSTRACT

An optical imaging lens includes a first, a second, a third, a fourth, a fifth, and a sixth lens elements from an object side to an image side arranged in order along an optical axis. The six lens elements are the only lens elements having refracting power in the optical imaging lens. An optical axis region of an object-side surface of the third lens element is concave. A periphery region of an image-side surface of the fourth lens element is concave. An optical axis region of an image-side surface of the sixth lens element is concave.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation application of and claims thepriority benefit of U.S. application Ser. No. 16/015,191, filed on Jun.22, 2018, now allowed. The prior U.S. application Ser. No. 16/015,191claims the priority benefit of China application serial no.201810294461.2, filed on Mar. 30, 2018. The entirety of each of theabove-mentioned patent applications is hereby incorporated by referenceherein and made a part of specification.

BACKGROUND OF THE INVENTION Technical Field

The invention relates to an optical imaging lens.

Description of Related Art

The specification of consumer electronic products is ever changing andthe demand for lighter, thinner, and smaller products never stopsgrowing, which is why the specification of key components (opticalimaging lenses and etc.) of the electronic products must also continueto be enhanced, so as to satisfy consumers' demands. The most importantfeatures of the optical imaging lenses include imaging quality andvolume. In addition, it is increasingly important to enhance field ofview as well as maintain a certain aperture size. When it comes toimaging quality, as image sensing technologies advance, the consumer'sdemands on imaging quality also become higher. Accordingly, in the fieldof optical lens design, apart from pursing slimness of lenses, theimaging quality and performance of lenses are required to be taken intoconsideration as well.

However, when designing an optical imaging lens, an optical lens havingboth a miniaturized size and a desirable imaging quality cannot bemanufactured by simply scaling down a lens with a desirable imagingquality. The design not only involves material properties but also needsto take practical production issues, such as manufacturing andassembling yield rates, into consideration.

The technical level of manufacturing a miniaturized lens is higher thanthat of manufacturing a traditional lens. Therefore, how to manufacturean optical imaging lens meeting the needs of consumer electronicproducts and facilitate the imaging quality of such optical lens hasbeen an issue of this field.

SUMMARY OF THE INVENTION

The invention provides an optical imaging lens capable of maintaining apreferable optical performance under a condition that a system length ofthe optical imaging lens is reduced.

An embodiment of the invention provides an optical imaging lensincluding a first lens element, a second lens element, a third lenselement, a fourth lens element, a fifth lens element, and a sixth lenselement sequentially arranged along an optical axis from an object sideto an image side. Each of the first to sixth lens elements includes anobject-side surface facing the object side and allowing imaging rays topass through and an image-side surface facing the image side andallowing the imaging rays to pass through. The six lens elements are theonly lens elements having refracting power in the optical imaging lens.An optical axis region of the object-side surface of the third lenselement is concave. A periphery region of the image-side surface of thefourth lens element is concave. An optical axis region of the image-sidesurface of the fifth lens element is convex. An optical axis region ofthe image-side surface of the sixth lens element is concave. The opticalimaging lens satisfies: (T1+G12)/(G23+G34+G56)≥3.600. T1 is a thicknessof the first lens element along the optical axis. G12 is an air gap fromthe first lens element to the second lens element along the opticalaxis. G23 is an air gap from the second lens element to the third lenselement along the optical axis. G34 is an air gap from the third lenselement to the fourth lens element along the optical axis. G56 is an airgap from the fifth lens element to the sixth lens element along theoptical axis.

An embodiment of the invention provides an optical imaging lensincluding a first lens element, a second lens element, a third lenselement, a fourth lens element, a fifth lens element, and a sixth lenselement sequentially arranged along an optical axis from an object sideto an image side. Each of the first to sixth lens elements includes anobject-side surface facing the object side and allowing imaging rays topass through and an image-side surface facing the image side andallowing the imaging rays to pass through. The six lens elements are theonly lens elements having refracting power in the optical imaging lens.An optical axis region of the object-side surface of the third lenselement is concave. An optical axis region of the image-side surface ofthe fourth lens element is concave, and a periphery region of theimage-side surface of the fourth lens element is concave. An opticalaxis region of the image-side surface of the sixth lens element isconcave, and a periphery region of the image-side surface of the sixthlens element is convex. The optical imaging lens satisfies:ALT/(G23+G34+G56)≥10.200. ALT is a sum of thicknesses of the first lenselement, the second lens element, the third lens element, the fourthlens element, the fifth lens element, and the sixth lens element alongthe optical axis. G23 is an air gap from the second lens element to thethird lens element along the optical axis. G34 is an air gap from thethird lens element to the fourth lens element along the optical axis.G56 is an air gap from the fifth lens element to the sixth lens elementalong the optical axis.

An embodiment of the invention provides an optical imaging lensincluding a first lens element, a second lens element, a third lenselement, a fourth lens element, a fifth lens element, and a sixth lenselement sequentially arranged along an optical axis from an object sideto an image side. Each of the first to sixth lens elements includes anobject-side surface facing the object side and allowing imaging rays topass through and an image-side surface facing the image side andallowing the imaging rays to pass through. The six lens elements are theonly lens elements having refracting power in the optical imaging lens.A periphery region of the image-side surface of the first lens elementis concave. An optical axis region of the object-side surface of thethird lens element is concave. A periphery region of the image-sidesurface of the fourth lens element is concave. An optical axis region ofthe image-side surface of the sixth lens element is concave. The opticalimaging lens satisfies: (G12+T5)/(G23+G34+G56)≥4.500. G12 is an air gapfrom the first lens element to the second lens element along the opticalaxis. T5 is a thickness of the fifth lens element along the opticalaxis. G23 is an air gap from the second lens element to the third lenselement along the optical axis. G34 is an air gap from the third lenselement to the fourth lens element along the optical axis. G56 is an airgap from the fifth lens element to the sixth lens element along theoptical axis.

Based on the above, the optical imaging lens according to theembodiments of the invention is effective in terms of the following. Bydesign and arranging the concave/convex shapes of the object-sidesurfaces or image-side surfaces of the lens elements, the opticalimaging lens is still provided with an optical performance capable ofovercoming aberrations and renders a greater field of view under thecondition that the system length of the optical imaging lens is reduced.

To make the aforementioned more comprehensible, several embodimentsaccompanied with drawings are described in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIG. 1 is a schematic diagram illustrating a surface shape structure ofa lens element.

FIG. 2 is a schematic diagram illustrating surface shape concave andconvex structures and a light focal point of a lens element.

FIG. 3 is a schematic diagram illustrating a surface shape structure ofa lens element according to Example 1.

FIG. 4 is a schematic diagram illustrating a surface shape structure ofa lens element according to Example 2.

FIG. 5 is a schematic diagram illustrating a surface shape structure ofa lens element according to Example 3.

FIG. 6 is a schematic diagram illustrating an optical imaging lensaccording to a first embodiment of the invention.

FIGS. 7A to 7D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the first embodiment.

FIG. 8 shows detailed optical data of the optical imaging lens accordingto the first embodiment of the invention.

FIG. 9 shows aspheric parameters pertaining to the optical imaging lensaccording to the first embodiment of the invention.

FIG. 10 is a schematic diagram illustrating an optical imaging lensaccording to a second embodiment of the invention.

FIGS. 11A to 11D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the second embodiment.

FIG. 12 shows detailed optical data of the optical imaging lensaccording to the second embodiment of the invention.

FIG. 13 shows aspheric parameters pertaining to the optical imaging lensaccording to the second embodiment of the invention.

FIG. 14 is a schematic diagram illustrating an optical imaging lensaccording to a third embodiment of the invention.

FIGS. 15A to 15D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the third embodiment.

FIG. 16 shows detailed optical data of the optical imaging lensaccording to the third embodiment of the invention.

FIG. 17 shows aspheric parameters pertaining to the optical imaging lensaccording to the third embodiment of the invention.

FIG. 18 is a schematic diagram illustrating an optical imaging lensaccording to a fourth embodiment of the invention.

FIGS. 19A to 19D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the fourth embodiment.

FIG. 20 shows detailed optical data of the optical imaging lensaccording to the fourth embodiment of the invention.

FIG. 21 shows aspheric parameters pertaining to the optical imaging lensaccording to the fourth embodiment of the invention.

FIG. 22 is a schematic diagram illustrating an optical imaging lensaccording to a fifth embodiment of the invention.

FIGS. 23A to 23D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the fifth embodiment.

FIG. 24 shows detailed optical data of the optical imaging lensaccording to the fifth embodiment of the invention.

FIG. 25 shows aspheric parameters pertaining to the optical imaging lensaccording to the fifth embodiment of the invention.

FIG. 26 is a schematic diagram illustrating an optical imaging lensaccording to a sixth embodiment of the invention.

FIGS. 27A to 27D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the sixth embodiment.

FIG. 28 shows detailed optical data of the optical imaging lensaccording to the sixth embodiment of the invention.

FIG. 29 shows aspheric parameters pertaining to the optical imaging lensaccording to the sixth embodiment of the invention.

FIG. 30 is a schematic diagram illustrating an optical imaging lensaccording to a seventh embodiment of the invention.

FIGS. 31A to 31D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the seventh embodiment.

FIG. 32 shows detailed optical data of the optical imaging lensaccording to the seventh embodiment of the invention.

FIG. 33 shows aspheric parameters pertaining to the optical imaging lensaccording to the seventh embodiment of the invention.

FIG. 34 is a schematic diagram illustrating an optical imaging lensaccording to an eighth embodiment of the invention.

FIGS. 35A to 35D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the eighth embodiment.

FIG. 36 shows detailed optical data of the optical imaging lensaccording to the eighth embodiment of the invention.

FIG. 37 shows aspheric parameters pertaining to the optical imaging lensaccording to the eighth embodiment of the invention.

FIG. 38 is a schematic diagram illustrating an optical imaging lensaccording to a ninth embodiment of the invention.

FIGS. 39A to 39D are diagrams illustrating a longitudinal sphericalaberration and various aberrations of the optical imaging lens accordingto the ninth embodiment.

FIG. 40 shows detailed optical data of the optical imaging lensaccording to the ninth embodiment of the invention.

FIG. 41 shows aspheric parameters pertaining to the optical imaging lensaccording to the ninth embodiment of the invention.

FIGS. 42 to 45 show values of respective important parameters andrelations thereof of the optical imaging lenses according to the firstto ninth embodiments of the invention.

DESCRIPTION OF THE EMBODIMENTS

In the present disclosure, the optical system may comprise at least onelens element to receive imaging rays that are incident on the opticalsystem over a set of angles ranging from parallel to an optical axis toa half field of view (HFOV) angle with respect to the optical axis. Theimaging rays pass through the optical system to produce an image on animage plane. The term “a lens element having positive refracting power(or negative refracting power)” means that the paraxial refracting powerof the lens element in Gaussian optics is positive (or negative). Theterm “an object-side (or image-side) surface of a lens element” refersto a specific region of that surface of the lens element at whichimaging rays can pass through that specific region. Imaging rays includeat least two types of rays: a chief ray Lc and a marginal ray Lm (asshown in FIG. 1 ). An object-side (or image-side) surface of a lenselement can be characterized as having several regions, including anoptical axis region, a periphery region, and, in some cases, one or moreintermediate regions, as discussed more fully below.

FIG. 1 is a radial cross-sectional view of a lens element 100. Tworeferential points for the surfaces of the lens element 100 can bedefined: a central point, and a transition point. The central point of asurface of a lens element is a point of intersection of that surface andthe optical axis I. As illustrated in FIG. 1 , a first central point CP1may be present on the object-side surface 110 of lens element 100 and asecond central point CP2 may be present on the image-side surface 120 ofthe lens element 100. The transition point is a point on a surface of alens element, at which the line tangent to that point is perpendicularto the optical axis I. The optical boundary OB of a surface of the lenselement is defined as a point at which the radially outermost marginalray Lm passing through the surface of the lens element intersects thesurface of the lens element. All transition points lie between theoptical axis I and the optical boundary OB of the surface of the lenselement. If multiple transition points are present on a single surface,then these transition points are sequentially named along the radialdirection of the surface with reference numerals starting from the firsttransition point. For example, the first transition point, e.g., TP1,(closest to the optical axis I), the second transition point, e.g., TP2,(as shown in FIG. 4 ), and the Nth transition point (farthest from theoptical axis I).

The region of a surface of the lens element from the central point tothe first transition point TP1 is defined as the optical axis region,which includes the central point. The region located radially outside ofthe farthest Nth transition point from the optical axis I to the opticalboundary OB of the surface of the lens element is defined as theperiphery region. In some embodiments, there may be intermediate regionspresent between the optical axis region and the periphery region, withthe number of intermediate regions depending on the number of thetransition points.

The shape of a region is convex if a collimated ray being parallel tothe optical axis I and passing through the region is bent toward theoptical axis I such that the ray intersects the optical axis I on theimage side A2 of the lens element. The shape of a region is concave ifthe extension line of a collimated ray being parallel to the opticalaxis I and passing through the region intersects the optical axis I onthe object side A1 of the lens element.

Additionally, referring to FIG. 1 , the lens element 100 may also have amounting portion 130 extending radially outward from the opticalboundary OB. The mounting portion 130 is typically used to physicallysecure the lens element to a corresponding element of the optical system(not shown). Imaging rays do not reach the mounting portion 130. Thestructure and shape of the mounting portion 130 are only examples toexplain the technologies, and should not be taken as limiting the scopeof the present disclosure. The mounting portion 130 of the lens elementsdiscussed below may be partially or completely omitted in the followingdrawings.

Referring to FIG. 2 , optical axis region Z1 is defined between centralpoint CP and first transition point TP1. Periphery region Z2 is definedbetween TP1 and the optical boundary OB of the surface of the lenselement. Collimated ray 211 intersects the optical axis I on the imageside A2 of lens element 200 after passing through optical axis regionZ1, i.e., the focal point of collimated ray 211 after passing throughoptical axis region Z1 is on the image side A2 of the lens element 200at point R in FIG. 2 . Accordingly, since the ray itself intersects theoptical axis I on the image side A2 of the lens element 200, opticalaxis region Z1 is convex. On the contrary, collimated ray 212 divergesafter passing through periphery region Z2. The extension line EL ofcollimated ray 212 after passing through periphery region Z2 intersectsthe optical axis I on the object side A1 of lens element 200, i.e., thefocal point of collimated ray 212 after passing through periphery regionZ2 is on the object side A1 at point M in FIG. 2 . Accordingly, sincethe extension line EL of the ray intersects the optical axis I on theobject side A1 of the lens element 200, periphery region Z2 is concave.In the lens element 200 illustrated in FIG. 2 , the first transitionpoint TP1 is the border of the optical axis region and the peripheryregion, i.e., TP1 is the point at which the shape changes from convex toconcave.

Alternatively, there is another way for a person having ordinary skillin the art to determine whether an optical axis region is convex orconcave by referring to the sign of “Radius” (the “R” value), which isthe paraxial radius of shape of a lens surface in the optical axisregion. The R value is commonly used in conventional optical designsoftware such as Zemax and CodeV. The R value usually appears in thelens data sheet in the software. For an object-side surface, a positiveR value defines that the optical axis region of the object-side surfaceis convex, and a negative R value defines that the optical axis regionof the object-side surface is concave. Conversely, for an image-sidesurface, a positive R value defines that the optical axis region of theimage-side surface is concave, and a negative R value defines that theoptical axis region of the image-side surface is convex. The resultfound by using this method should be consistent with the methodutilizing intersection of the optical axis by rays/extension linesmentioned above, which determines surface shape by referring to whetherthe focal point of a collimated ray being parallel to the optical axis Iis on the object-side or the image-side of a lens element. As usedherein, the terms “a shape of a region is convex (concave),” “a regionis convex (concave),” and “a convex- (concave-) region,” can be usedalternatively.

FIG. 3 , FIG. 4 and FIG. 5 illustrate examples of determining the shapeof lens element regions and the boundaries of regions under variouscircumstances, including the optical axis region, the periphery region,and intermediate regions as set forth in the present specification.

FIG. 3 is a radial cross-sectional view of a lens element 300. Asillustrated in FIG. 3 , only one transition point TP1 appears within theoptical boundary OB of the image-side surface 320 of the lens element300. Optical axis region Z1 and periphery region Z2 of the image-sidesurface 320 of lens element 300 are illustrated. The R value of theimage-side surface 320 is positive (i.e., R>0). Accordingly, the opticalaxis region Z1 is concave.

In general, the shape of each region demarcated by the transition pointwill have an opposite shape to the shape of the adjacent region(s).Accordingly, the transition point will define a transition in shape,changing from concave to convex at the transition point or changing fromconvex to concave. In FIG. 3 , since the shape of the optical axisregion Z1 is concave, the shape of the periphery region Z2 will beconvex as the shape changes at the transition point TP1.

FIG. 4 is a radial cross-sectional view of a lens element 400. Referringto FIG. 4 , a first transition point TP1 and a second transition pointTP2 are present on the object-side surface 410 of lens element 400. Theoptical axis region Z1 of the object-side surface 410 is defined betweenthe optical axis I and the first transition point TP1. The R value ofthe object-side surface 410 is positive (i.e., R>0). Accordingly, theoptical axis region Z1 is convex.

The periphery region Z2 of the object-side surface 410, which is alsoconvex, is defined between the second transition point TP2 and theoptical boundary OB of the object-side surface 410 of the lens element400. Further, intermediate region Z3 of the object-side surface 410,which is concave, is defined between the first transition point TP1 andthe second transition point TP2. Referring once again to FIG. 4 , theobject-side surface 410 includes an optical axis region Z1 locatedbetween the optical axis I and the first transition point TP1, anintermediate region Z3 located between the first transition point TP1and the second transition point TP2, and a periphery region Z2 locatedbetween the second transition point TP2 and the optical boundary OB ofthe object-side surface 410. Since the shape of the optical axis regionZ1 is designed to be convex, the shape of the intermediate region Z3 isconcave as the shape of the intermediate region Z3 changes at the firsttransition point TP1, and the shape of the periphery region Z2 is convexas the shape of the periphery region Z2 changes at the second transitionpoint TP2.

FIG. 5 is a radial cross-sectional view of a lens element 500. Lenselement 500 has no transition point on the object-side surface 510 ofthe lens element 500. For a surface of a lens element with no transitionpoint, for example, the object-side surface 510 the lens element 500,the optical axis region Z1 is defined as the region between 0-50% of thedistance between the optical axis I and the optical boundary OB of thesurface of the lens element and the periphery region is defined as theregion between 50%-100% of the distance between the optical axis I andthe optical boundary OB of the surface of the lens element. Referring tolens element 500 illustrated in FIG. 5 , the optical axis region Z1 ofthe object-side surface 510 is defined between the optical axis I and50% of the distance between the optical axis I and the optical boundaryOB. The R value of the object-side surface 510 is positive (i.e., R>0).Accordingly, the optical axis region Z1 is convex. For the object-sidesurface 510 of the lens element 500, because there is no transitionpoint, the periphery region Z2 of the object-side surface 510 is alsoconvex. It should be noted that lens element 500 may have a mountingportion (not shown) extending radially outward from the periphery regionZ2.

FIG. 6 is a schematic diagram illustrating an optical imaging lensaccording to a first embodiment of the invention. FIGS. 7A to 7D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the firstembodiment. Referring to FIG. 6 , an optical imaging lens 10 includes afirst lens element 1, an aperture 0, a second lens element 2, a thirdlens element 3, a fourth lens element 4, a fifth lens element 5, a sixthlens element 6, and a filter 9 sequentially arranged from an object sideto an image side along an optical axis I. When a ray emitted from anobject to be shot enters the optical imaging lens 10, an image may beformed on an image plane 99 after the ray passes through the first lenselement 1, the aperture 0, the second lens element 2, the third lenselement 3, the fourth lens element 4, the fifth lens element 5, thesixth lens element 6, and the filter 9. The filter 9 may be an infraredcut-off filter, for example, and is adapted to prevent a portion ofinfrared light in the ray from being transmitted to the image plane 99and affecting the imaging quality. It is noted that, the object side isa side facing the object to be shot, whereas the image side is a sidefacing the image plane 99.

The first lens element 1, the second lens element 2, the third lenselement 3, the fourth lens element 4, the fifth lens element 5, thesixth lens element 6, and the filter 9 respectively have object-sidesurfaces 15, 25, 35, 45, 55, 65, and 95 facing the object side andallowing imaging rays to pass through and image-side surfaces 16, 26,36, 46, 56, 66, and 96 facing the image side and allowing the imagingrays to pass through.

To meet the needs for weight reduction of the product, materials of thefirst lens element 1 to the sixth lens element 6 may be plastic.However, the materials of the first lens element 1 to the sixth lenselement 6 are not limited thereto.

The first lens element 1 has negative refracting power. On theobject-side surface 15 of the first lens element 1, an optical axisregion 152 is concave, and a periphery region 153 is convex. Inaddition, on the image-side surface 16 of the first lens element 1, anoptical axis region 162 and a periphery region 164 are both concave.

The second lens element 2 has positive refracting power. On theobject-side surface 25 of the second lens element 2, an optical axisregion 251 and a periphery region 253 are both convex. In addition, onthe image-side surface 26 of the second lens element 2, an optical axisregion 261 and a periphery region 263 are both convex.

The third lens element 3 has positive refracting power. On theobject-side surface 35 of the third lens element 3, an optical axisregion 352 and a periphery region 354 are both concave. In addition, onthe image-side surface 36 of the second lens element 3, an optical axisregion 361 and a periphery region 363 are both convex.

The fourth lens element 4 has negative refracting power. On theobject-side surface 45 of the fourth lens element 4, an optical axisregion 451 is convex, and a periphery region 454 is concave. Inaddition, on the image-side surface 46 of the fourth lens element 4, anoptical axis region 462 is concave, and a periphery region 463 isconvex.

The fifth lens element 5 has positive refracting power. On theobject-side surface 55 of the fifth lens element 5, an optical axisregion 552 and a periphery region 554 are both concave. In addition, onthe image-side surface 56 of the fifth lens element 5, an optical axisregion 561 and a periphery region 563 are both convex.

The sixth lens element 6 has negative refracting power. On theobject-side surface 65 of the sixth lens element 6, an optical axisregion 651 is convex, and a periphery region 654 is concave. Inaddition, on the image-side surface 66 of the sixth lens element 6, anoptical axis region 662 is concave, and a periphery region 663 isconvex.

In the optical imaging lens 10, only the above lens elements haverefracting power, and the number of lens elements having refractingpower in the optical imaging lens 10 is six.

Other detailed optical data of the first embodiment are as shown in FIG.8 . The system length (TTL) of the whole optical imaging lens 10 of thefirst embodiment is 5.411 mm, the effective focal length (EFL) thereofis 2.115 mm, the half field of view (HFOV) thereof is 58.533°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250. Thesystem length refers to a distance from the object-side surface 15 ofthe first lens element 1 to the image plane 99 along the optical axis I.

Besides, in the embodiment, the object-side surfaces and the image-sidesurfaces of the six lens elements, totaling 12 surfaces, are allaspheric surfaces. In addition, the aspheric surfaces are defined basedon the following equation:

$\begin{matrix}{{Z(Y)} = {{\frac{Y^{2}}{R}/\left( {1 + \sqrt{1 - {\left( {1 + K} \right)\frac{Y^{2}}{R^{2}}}}} \right)} + {\sum\limits_{i = 1}^{n}{a_{2i} \times Y^{i}}}}} & (1)\end{matrix}$

wherein:

Y represents a vertical distance from a point on an aspheric curve tothe optical axis I;

Z represents a depth of an aspheric surface (a vertical distance betweenthe point on the aspheric surface that is spaced by the distance Y fromthe optical axis I and a tangent plane tangent to a vertex of theaspheric surface on the optical axis I);

R represents a radius of curvature of the surface of the lens elementproximate the optical axis I;

K represents a conic constant;

a_(2i) represents a 2i^(th) aspheric coefficient.

Respective aspheric coefficients of the object-side surfaces 15, 25, 35,45, 55, and 65 and the image-side surfaces 16, 26, 36, 46, 56, and 66 inEquation (1) are as shown in FIG. 9 . For example, the row number 15 inFIG. 9 indicates the aspheric coefficients of the object-side surface 15of the first lens element 1. Other rows are arranged based on the sameprinciple.

In addition, relations of important parameters in the optical imaginglens 10 according to the first embodiment are as shown in FIGS. 42 and43 . In the optical imaging lens 10 of the first embodiment,

V1 is an Abbe number of the first lens element 1, wherein the Abbenumber may also be referred to as a dispersion coefficient;

V2 is an Abbe number of the second lens element 2;

V3 is an Abbe number of the third lens element 3;

V4 is an Abbe number of the fourth lens element 4;

V5 is an Abbe number of the fifth lens element 5;

V6 is an Abbe number of the sixth lens element 6;

T1 is a thickness of the first lens element 1 along the optical axis I;

T2 is a thickness of the second lens element 2 along the optical axis I;

T3 is a thickness of the third lens element 3 along the optical axis I;

T4 is a thickness of the fourth lens element 4 along the optical axis I;

T5 is a thickness of the fifth lens element 5 along the optical axis I;

T6 is a thickness of the sixth lens element 6 along the optical axis I;

TF is a thickness of the filter 9 along the optical axis I;

G12 is an air gap from the first lens element 1 to the second lenselement 2 along the optical axis I;

G23 is an air gap from the second lens element 2 to the third lenselement 3 along the optical axis I;

G34 is an air gap from the third lens element 3 to the fourth lenselement 4 along the optical axis I;

G45 is an air gap from the fourth lens element 4 to the fifth lenselement 5 along the optical axis I;

G56 is an air gap from the fifth lens element 5 to the sixth lenselement 6 along the optical axis I;

G6F is an air gap from the sixth lens element 6 to the filter 9 alongthe optical axis I;

GFP is an air gap from the filter 9 to the image plane 99 along theoptical axis I;

AAG is a sum of the five air gaps from the first lens element 1 to thesixth lens element 6 along the optical axis I, i.e. the sum of the G12,G23, G34, G45, and G56;

ALT is a sum of the thicknesses of the first lens element 1, the secondlens element 2, the third lens element 3, the fourth lens element 4, thefifth lens element 5, and the sixth lens element 6 along the opticalaxis I, i.e. the sum of the T1, T2, T3, T4, T5, and T6;

EFL is an effective focal length of the optical imaging lens 10;

BFL is a distance from the image-side surface 66 of the sixth lenselement 6 to the image plane 99 along the optical axis I;

TTL is a distance from the object-side surface 15 of the first lenselement 1 to the image plane 99 along the optical axis I;

TL is a distance from the object-side surface 15 of the first lenselement 1 to the image-side surface 66 of the sixth lens element 6 alongthe optical axis I; and

HFOV is a half field of view of the optical imaging lens 10.

Referring to FIGS. 7A to 7D, FIG. 7A illustrates the longitudinalspherical aberration of optical imaging lens 10 of the first embodimentwhen the pupil radius is 0.4701 mm. In FIG. 7A, the curves representingthe respective wavelengths are close to each other and approach thecenter, indicating that off-axis rays in different heights at therespective wavelengths are concentrated in a vicinity of the imagingpoint. Based on extents of deviation of the curves for the respectivewavelengths, imaging point deviations of the off-axis rays in differentheights are controlled within a range from −0.04 mm to 0.01 mm.Therefore, the spherical aberration of the same wavelength is reduced inthe optical imaging lens of the first embodiment. In addition, thedistances among the three representing wavelengths are close, indicatingthat imaging positions of rays of different wavelengths areconcentrated. Hence, chromatic aberration is also suppressed.

FIGS. 7B and 7C respectively illustrate the field curvature aberrationin the sagittal direction and the field curvature aberration in thetangential direction on the image plane 99 when the wavelength is 650mm, 555 mm, and 470 mm. In FIGS. 7B and 7C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.04 mm to 0.14 mm, indicating that the optical imaging lens ofthe first embodiment is able to effectively reduce aberration.

FIG. 7D illustrates the distortion aberration on the image plane 99 whenthe wavelength is 650 mm, 555 mm, and 470 mm. FIG. 7D illustrating thedistortion aberration indicates that the distortion aberration ismaintained within a range from −18% to 3%, indicating that thedistortion aberration of the optical imaging lens of the firstembodiment already satisfies the imaging quality requirement of anoptical system.

Based on the above, compared with known optical lenses, the opticalimaging lens of the first embodiment is able to render a desirableimaging quality under a condition that the system length is reduced toabout 5.411 mm. Besides, in the optical imaging lens of the firstembodiment, the system length is reduced and the shooting angle isexpanded under a condition of maintaining a desirable opticalperformance. Thus, a product design capable of miniaturization andexpanding the field of view is achieved.

FIG. 10 is a schematic diagram illustrating an optical imaging lensaccording to a second embodiment of the invention. FIGS. 11A to 11D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the secondembodiment. Referring to FIG. 10 , the second embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. In addition, a periphery region564 of the image-side surface 56 of the fifth lens element 5 is concave.To clearly illustrate the drawing, some reference numerals indicatingsurface shapes same as those of the first embodiment are omitted in FIG.10 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 12 . The system length (TTL) of the optical imaging lens 10 of thesecond embodiment is 4.865 mm, the effective focal length (EFL) thereofis 2.497 mm, the half field of view (HFOV) thereof is 58.439°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the second embodiment inEquation (1) are shown in FIG. 13 .

In addition, relations of important parameters in the optical imaginglens 10 according to the second embodiment are as shown in FIGS. 42 and43 .

Referring to FIGS. 11A to 11D, in FIG. 11A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.02 mm to 0.14 mm when thepupil radius is 0.5548 mm. In FIGS. 11B and 11C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.60 mm to 0.14 mm. In FIG. 11D illustrating the distortionaberration, the distortion aberration is maintained within a range from−25% to 0%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the second embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 4.865 mm.

In addition, based on the above, the second embodiment is more desirableover the first embodiment in that the system length of the secondembodiment is less than that of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the second embodiment is less than thatof the first embodiment, the lens elements in the second embodiment areeasier to be manufactured and thus have higher yield.

FIG. 14 is a schematic diagram illustrating an optical imaging lensaccording to a third embodiment of the invention. FIGS. 15A to 15D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the thirdembodiment. Referring to FIG. 14 , the third embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. In addition, a periphery region564 of the image-side surface 56 of the fifth lens element 5 is concave.To clearly illustrate the drawing, some reference numerals indicatingsurface shapes same as those of the first embodiment are omitted in FIG.14 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 16 . The system length (TTL) of the optical imaging lens 10 of thethird embodiment is 5.600 mm, the effective focal length (EFL) thereofis 2.173 mm, the half field of view (HFOV) thereof is 58.459°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the third embodiment inEquation (1) are shown in FIG. 17 .

In addition, relations of important parameters in the optical imaginglens 10 according to the third embodiment are as shown in FIGS. 42 and43 .

Referring to FIGS. 15A to 15D, in FIG. 15A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.045 mm to 0.025 mm when thepupil radius is 0.4828 mm. In FIGS. 15B and 15C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.08 mm to 0.06 mm. In FIG. 15D illustrating the distortionaberration, the distortion aberration is maintained within a range from−20% to 4%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the third embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 5.600 mm.

In addition, based on the above, the third embodiment is more desirableover the first embodiment in that the field curvature aberration of thethird embodiment is less than that of the first embodiment. Besides,because a thickness difference between the optical axis regions and theperiphery regions of the lens elements in the third embodiment is lessthan that of the first embodiment, the lens elements in the thirdembodiment are easier to be manufactured and thus have higher yield.

FIG. 18 is a schematic diagram illustrating an optical imaging lensaccording to a fourth embodiment of the invention. FIGS. 19A to 19D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the fourthembodiment. Referring to FIG. 18 , the fourth embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. In addition, a periphery region464 of the image-side surface 46 of the fourth lens element 4 isconcave, and a periphery region 553 of the object-side surface 55 of thefifth lens element 5 is convex. To clearly illustrate the drawing, somereference numerals indicating surface shapes same as those of the firstembodiment are omitted in FIG. 18 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 20 . The system length (TTL) of the optical imaging lens 10 of thefourth embodiment is 5.014 mm, the effective focal length (EFL) thereofis 2.157 mm, the half field of view (HFOV) thereof is 58.520°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the fourth embodiment inEquation (1) are shown in FIG. 21 .

In addition, relations of important parameters in the optical imaginglens 10 according to the fourth embodiment are as shown in FIGS. 42 and43 .

Referring to FIGS. 19A to 19D, in FIG. 19A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.035 mm to 0.015 mm when thepupil radius is 0.4793 mm. In FIGS. 19B and 19C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.07 mm to 0.06 mm. In FIG. 19D illustrating the distortionaberration, the distortion aberration is maintained within a range from−20% to 1%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the fourth embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 5.014 mm.

In addition, based on the above, the fourth embodiment is more desirableover the first embodiment in that the system length of the fourthembodiment is less than that of the first embodiment. The longitudinalspherical aberration, the field curvature aberration, and the distortionaberration of the fourth embodiment are respectively less than thelongitudinal spherical aberration, the field curvature aberration, andthe distortion aberration of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the fourth embodiment is less than thatof the first embodiment, the lens elements in the fourth embodiment areeasier to be manufactured and thus have higher yield.

FIG. 22 is a schematic diagram illustrating an optical imaging lensaccording to a fifth embodiment of the invention. FIGS. 23A to 23D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the fifthembodiment. Referring to FIG. 22 , the fifth embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. Besides, the third lens element 3has negative refracting power. The periphery region 464 of theimage-side surface 46 of the fourth lens element 4 is concave. Theperiphery region 553 of the object-side surface 55 of the fifth lenselement 5 is convex. To clearly illustrate the drawing, some referencenumerals indicating surface shapes same as those of the first embodimentare omitted in FIG. 22 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 24 . The system length (TTL) of the optical imaging lens 10 of thefifth embodiment is 4.790 mm, the effective focal length (EFL) thereofis 2.117 mm, the half field of view (HFOV) thereof is 58.438°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the fifth embodiment inEquation (1) are shown in FIG. 25 .

In addition, relations of important parameters in the optical imaginglens 10 according to the fifth embodiment are as shown in FIGS. 42 and43 .

Referring to FIGS. 23A to 23D, in FIG. 23A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.03 mm to 0.015 mm when thepupil radius is 0.4704 mm. In FIGS. 23B and 23C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.12 mm to 0.04 mm. In FIG. 23D illustrating the distortionaberration, the distortion aberration is maintained within a range from−18% to 0%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the fifth embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 4.790 mm.

In addition, based on the above, the fifth embodiment is more desirableover the first embodiment in that the system length of the fifthembodiment is less than that of the first embodiment. The longitudinalspherical aberration, the field curvature aberration, and the distortionaberration of the fifth embodiment are respectively less than thelongitudinal spherical aberration, the field curvature aberration, andthe distortion aberration of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the fifth embodiment is less than thatof the first embodiment, the lens elements in the fifth embodiment areeasier to be manufactured and thus have higher yield.

FIG. 26 is a schematic diagram illustrating an optical imaging lensaccording to a sixth embodiment of the invention. FIGS. 27A to 27D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the sixthembodiment. Referring to FIG. 26 , the sixth embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. To clearly illustrate the drawing,some reference numerals indicating surface shapes same as those of thefirst embodiment are omitted in FIG. 26 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 28 . The system length (TTL) of the optical imaging lens 10 of thesixth embodiment is 5.035 mm, the effective focal length (EFL) thereofis 2.086 mm, the half field of view (HFOV) thereof is 58.519°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the sixth embodiment inEquation (1) are shown in FIG. 29 .

In addition, relations of important parameters in the optical imaginglens 10 according to the sixth embodiment are as shown in FIGS. 44 and45 .

Referring to FIGS. 27A to 27D, in FIG. 27A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.07 mm to 0.02 mm when thepupil radius is 0.4634 mm. In FIGS. 27B and 27C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.13 mm to 0.05 mm. In FIG. 27D illustrating the distortionaberration, the distortion aberration is maintained within a range from−18% to 2%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the sixth embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 5.035 mm.

In addition, based on the above, the sixth embodiment is more desirableover the first embodiment in that the system length of the sixthembodiment is less than that of the first embodiment. The fieldcurvature aberration and the distortion aberration of the sixthembodiment are respectively less than the field curvature aberration andthe distortion aberration of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the sixth embodiment is less than thatof the first embodiment, the lens elements in the sixth embodiment areeasier to be manufactured and thus have higher yield.

FIG. 30 is a schematic diagram illustrating an optical imaging lensaccording to a seventh embodiment of the invention. FIGS. 31A to 31D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the seventhembodiment. Referring to FIG. 30 , the seventh embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. Besides, an optical axis region151 of the object-side surface 15 of the first lens element 1 is convex.A periphery region 353 of the object-side surface 35 of the third lenselement 3 is convex. The periphery region 464 of the image-side surface46 of the fourth lens element 4 is concave. To clearly illustrate thedrawing, some reference numerals indicating surface shapes same as thoseof the first embodiment are omitted in FIG. 30 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 32 . The system length (TTL) of the optical imaging lens 10 of theseventh embodiment is 4.673 mm, the effective focal length (EFL) thereofis 2.285 mm, the half field of view (HFOV) thereof is 58.520°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the seventh embodimentin Equation (1) are shown in FIG. 33 .

In addition, relations of important parameters in the optical imaginglens 10 according to the seventh embodiment are as shown in FIGS. 44 and45 .

Referring to FIGS. 31A to 31D, in FIG. 31A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.02 mm to 0.012 mm when thepupil radius is 0.5078 mm. In FIGS. 31B and 31C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.30 mm to 0.10 mm. In FIG. 31D illustrating the distortionaberration, the distortion aberration is maintained within a range from−25% to 0%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the seventh embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 4.673 mm.

In addition, based on the above, the seventh embodiment is moredesirable over the first embodiment in that the system length of theseventh embodiment is less than that of the first embodiment. Thelongitudinal spherical aberration of the seventh embodiment is less thanthe longitudinal spherical aberration of the first embodiment. Besides,because a thickness difference between the optical axis regions and theperiphery regions of the lens elements in the seventh embodiment is lessthan that of the first embodiment, the lens elements in the seventhembodiment are easier to be manufactured and thus have higher yield.

FIG. 34 is a schematic diagram illustrating an optical imaging lensaccording to an eighth embodiment of the invention. FIGS. 35A to 35D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the eighthembodiment. Referring to FIG. 34 , the eighth embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. In addition, a periphery region464 of the image-side surface 46 of the fourth lens element 4 isconcave, and a periphery region 553 of the object-side surface 55 of thefifth lens element 5 is convex. To clearly illustrate the drawing, somereference numerals indicating surface shapes same as those of the firstembodiment are omitted in FIG. 34 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 36 . The system length (TTL) of the optical imaging lens 10 of theeighth embodiment is 5.052 mm, the effective focal length (EFL) thereofis 2.202 mm, the half field of view (HFOV) thereof is 58.521°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the eighth embodiment inEquation (1) are shown in FIG. 37 .

In addition, relations of important parameters in the optical imaginglens 10 according to the eighth embodiment are as shown in FIGS. 44 and45 .

Referring to FIGS. 35A to 35D, in FIG. 35A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.025 mm to 0.015 mm when thepupil radius is 0.4892 mm. In FIGS. 35B and 35C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.08 mm to 0.10 mm. In FIG. 35D illustrating the distortionaberration, the distortion aberration is maintained within a range from−21% to 0%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the eighth embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 5.052 mm.

In addition, based on the above, the eighth embodiment is more desirableover the first embodiment in that the system length of the eighthembodiment is less than that of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the eighth embodiment is less than thatof the first embodiment, the lens elements in the eighth embodiment areeasier to be manufactured and thus have higher yield.

FIG. 38 is a schematic diagram illustrating an optical imaging lensaccording to a ninth embodiment of the invention. FIGS. 39A to 39D arediagrams illustrating a longitudinal spherical aberration and variousaberrations of the optical imaging lens according to the ninthembodiment. Referring to FIG. 38 , the ninth embodiment of the opticalimaging lens 10 is similar to the first embodiment, and the differencestherebetween mainly include the following: respective optical data,aspheric coefficients and parameters among the lens elements aredifferent to a more or lesser extent. In addition, a periphery region464 of the image-side surface 46 of the fourth lens element 4 isconcave, and a periphery region 553 of the object-side surface 55 of thefifth lens element 5 is convex. To clearly illustrate the drawing, somereference numerals indicating surface shapes same as those of the firstembodiment are omitted in FIG. 38 .

Detailed optical data of the optical imaging lens 10 are as shown inFIG. 40 . The system length (TTL) of the optical imaging lens 10 of theninth embodiment is 4.913 mm, the effective focal length (EFL) thereofis 2.247 mm, the half field of view (HFOV) thereof is 58.522°, the imageheight thereof is 2.880 mm, and the f-number (Fno) thereof is 2.250.

Respective aspheric coefficients of the object-side surfaces and theimage-side surfaces of the six lens elements of the ninth embodiment inEquation (1) are shown in FIG. 41 .

In addition, relations of important parameters in the optical imaginglens 10 according to the ninth embodiment are as shown in FIGS. 44 and45 .

Referring to FIGS. 39A to 39D, in FIG. 39A illustrating the longitudinalspherical aberration, imaging point deviations of the off-axis rays indifferent heights are controlled within −0.05 mm to 0.02 mm when thepupil radius is 0.4993 mm. In FIGS. 39B and 39C illustrating the fieldcurvature aberrations, the field curvature aberrations of the threerepresenting wavelengths in the whole field range fall within a rangefrom −0.06 mm to 0.08 mm. In FIG. 39D illustrating the distortionaberration, the distortion aberration is maintained within a range from−25% to 0%. Based on the above, compared with known optical lenses, theoptical imaging lens 10 of the ninth embodiment is able to render adesirable imaging quality under a condition that the system length isreduced to about 4.913 mm.

In addition, based on the above, the ninth embodiment is more desirableover the first embodiment in that the system length of the ninthembodiment is less than that of the first embodiment. The fieldcurvature aberration of the ninth embodiment is less than the fieldcurvature aberration of the first embodiment. Besides, because athickness difference between the optical axis regions and the peripheryregions of the lens elements in the ninth embodiment is less than thatof the first embodiment, the lens elements in the ninth embodiment areeasier to be manufactured and thus have higher yield.

In the respective embodiments of the invention, light can be effectivelyconverged as the optical axis region of the image-side surface of thesecond lens element is convex, and in coordination with that the opticalaxis region of the object-side surface of the third lens element isconcave. Since the optical axis region of the object-side surface of thefifth lens element is concave, the fifth lens element has positiverefracting power, and in coordination with that the optical axis regionof the object side surface of the fourth lens element is convex orAAG/T4≤5.0 or AAG/T5≤1.8, it is beneficial for the correction of theaberrations under a premise that a greater field of view is provided.Herein, a preferable range of AAG/T4 is 3.000 to 5.000, and a preferablerange of AAG/T5 is 0.900 to 1.800. When V3-V6≥20.000 is satisfied, thesystem length can be reduced and the imaging quality can be ensured,wherein a preferable range of V3-V6 is 20.000 to 40.000.

In order to reduce the system length and ensure the imaging quality, theair gap between lens elements or the thickness of the lens element maybe suitably reduced.

Nevertheless, considering the manufacturing complexity, a configurationis desirable if at least one of the following condition expressions issatisfied.3.600≤(T1+G12)/(G23+G34+G56), preferably3.600≤(T1+G12)/(G23+G34+G56)≤5.700;4.600≤EFL/(T3+G56), preferably 4.600≤EFL/(T3+G56)≤6.800;AAG/T2≤4.000, preferably 1.600≤AAG/T2≤4.000;3.700≤ALT/(T4+G56), preferably 3.700≤ALT/(T4+G56)≤10.000;10.200≤ALT/(G23+G34+G56), preferably 10.200≤ALT/(G23+G34+G56)≤18.200;AAG/G45≤6.000, preferably 2.900≤AAG/G45≤6.000;EFL/T5≤4.200, preferably 2.200≤EFL/T5≤4.200;3.100≤BFL/T3, preferably 3.100≤BFL/T3≤6.000;4.500≤(G12+T5)/(G23+G34+G56), preferably4.500≤(G12+T5)/(G23+G34+G56)≤9.000; and6.200≤ALT/(T3+G56), preferably 6.200≤ALT/(T3+G56)≤9.300.

If at least one of the following condition expressions is satisfied, theratio of the optical element parameters to the system length ismaintained to be within an appropriate range, so as to prevent theoptical element parameters from becoming too small, which is detrimentalto the production of the optical imaging lens, or to prevent the opticalelement parameters from becoming too large, which may lead to excessivesystem length.TTL/(T1+T5)≤4.800, preferably 3.900≤TTL/(T1+T5)≤4.800;TTL/T5≤7.800, preferably 5.300≤TTL/T5≤7.800;TTL/(T5+T6)≤6.000, preferably 3.200≤TTL/(T5+T6)≤6.000;13.800≤TTL/(T4+G56), preferably 13.800≤TTL/(T4+G56)≤17.000;TL/(T1+T5)≤4.100, preferably 2.900≤TL/(T1+T5)≤4.100;TTL/(T2+T6)≤5.100, preferably 4.400≤TTL/(T2+T6)≤5.100; andTL/(T3+T5)≤4.000, preferably 3.000≤TL/(T3+T5)≤4.000.

In addition, it is optional to select a random combination relationshipof the parameter in the embodiment to increase limitation of the opticalimaging lens for the ease of designing the optical imaging lens havingthe same structure in the invention. Considering the unpredictability inthe design of optical system, under the framework of the embodiments ofthe invention, the embodiments of the invention may have shorter systemlength, greater aperture availability, desirable imaging quality, or afacilitated assembling yield rate if the above condition expressions aresatisfied so as to improve the shortcoming of prior art.

An arbitrary number of the exemplary limiting relations listed above mayalso be arbitrarily and optionally combined and incorporated into theembodiments of the invention. The invention shall not be construed asbeing limited thereto. In implementation of the invention, apart fromthe above-described relations, it is also possible to add additionaldetailed structure such as more concave and convex curvaturesarrangement of a specific lens element or a plurality of lens elementsso as to enhance control of system property and/or resolution. It shouldbe noted that the above-described details can be optionally combined andapplied to the other embodiments of the invention under the conditionwhere they are not in conflict with one another.

In view of the foregoing, the optical imaging lens according to one orsome exemplary embodiments of the invention is able to render one orsome of the following:

i. The longitudinal spherical aberrations, field curvature aberrations,and distortion aberrations of the respective embodiments of theinvention meet the protocol of use. In addition, the off-axis rays ofthe three representing wavelengths, i.e., 650 nm, 555 nm, and 470 nm, indifferent heights are all concentrated at a vicinity of the imagingpoint. The extents of deviation of the respective curves show that theimaging point deviations of the off-axis rays in different heights arecontrolled, so a desirable suppressing ability against sphericalaberration, image aberration, and distortion aberration is rendered. Theimaging quality data further suggest that the distances among the threerepresenting wavelengths, i.e., 650 nm, 555 nm, and 470 nm, are close toeach other, indicating that the embodiments of the invention are able todesirably concentrate rays of different wavelengths in various statesand exhibit an excellent dispersion suppressing ability. Therefore, theembodiments of the invention render a desirable optical performance.

ii. An arbitrary number of the exemplary limiting relations listed abovemay also be arbitrarily and optionally combined and incorporated intothe embodiments of the invention. The invention shall not be construedas being limited thereto.

iii. The maximum and minimum numeral values derived from thecombinations of the optical parameters disclosed in the embodiments ofthe invention may all be applicable and enable people skill in thepertinent art to implement the invention.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the disclosed embodimentswithout departing from the scope or spirit of the disclosure. In view ofthe foregoing, it is intended that the disclosure covers modificationsand variations provided that they fall within the scope of the followingclaims and their equivalents.

What is claimed is:
 1. An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element sequentially arranged along an optical axis from an object side to an image side, each of the first lens element to the sixth lens element comprising an object-side surface facing the object side and allowing imaging rays to pass through and an image-side surface facing the image side and allowing the imaging rays to pass through, the six lens elements being the only lens elements having refracting power in the optical imaging lens, wherein an optical axis region of the object-side surface of the third lens element is concave; a periphery region of the image-side surface of the fourth lens element is concave; an optical axis region of the image-side surface of the fifth lens element is convex; an optical axis region of the image-side surface of the sixth lens element is concave; and the optical imaging lens satisfies: (T1+G12)/(G23+G34+G56)≥3.600, wherein T1 is a thickness of the first lens element along the optical axis, G12 is an air gap from the first lens element to the second lens element along the optical axis, G23 is an air gap from the second lens element to the third lens element along the optical axis, G34 is an air gap from the third lens element to the fourth lens element along the optical axis, and G56 is an air gap from the fifth lens element to the sixth lens element along the optical axis.
 2. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: ALT/(T3+G56)≥6.200, wherein ALT is a sum of thicknesses of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element along the optical axis, and T3 is a thickness of the third lens element along the optical axis.
 3. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: AAG/T2≤4.000, wherein AAG is a sum of five air gaps from the first lens element to the sixth lens element along the optical axis, and T2 is a thickness of the second lens element along the optical axis.
 4. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: TTL/(T1+T5)≤4.800, wherein TTL is a distance from the object-side surface of the first lens element to an image plane along the optical axis, and T5 is a thickness of the fifth lens element along the optical axis.
 5. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: ALT/(T4+G56)≥3.700, wherein ALT is a sum of thicknesses of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element along the optical axis, and T4 is a thickness of the fourth lens element along the optical axis.
 6. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: AAG/T4≤5.000, wherein AAG is a sum of five air gaps from the first lens element to the sixth lens element along the optical axis, and T4 is a thickness of the fourth lens element along the optical axis.
 7. The optical imaging lens as claimed in claim 1, wherein the optical imaging lens satisfies: TTL/(T5+T6)≤6.000, wherein TTL is a distance from the object-side surface of the first lens element to an image plane along the optical axis, T5 is a thickness of the fifth lens element along the optical axis, and T6 is a thickness of the sixth lens element along the optical axis.
 8. An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element sequentially arranged along an optical axis from an object side to an image side, each of the first lens element to the sixth lens element comprising an object-side surface facing the object side and allowing imaging rays to pass through and an image-side surface facing the image side and allowing the imaging rays to pass through, the six lens elements being the only lens elements having refracting power in the optical imaging lens, wherein an optical axis region of the object-side surface of the third lens element is concave; an optical axis region of the image-side surface of the fourth lens element is concave, and a periphery region of the image-side surface of the fourth lens element is concave; an optical axis region of the image-side surface of the sixth lens element is concave, and a periphery region of the image-side surface of the sixth lens element is convex; and the optical imaging lens satisfies: ALT/(G23+G34+G56)≥10.200, wherein ALT is a sum of thicknesses of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element along the optical axis, G23 is an air gap from the second lens element to the third lens element along the optical axis, G34 is an air gap from the third lens element to the fourth lens element along the optical axis, and G56 is an air gap from the fifth lens element to the sixth lens element along the optical axis.
 9. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: EFL/(T3+G56)≥4.600, wherein EFL is an effective focal length of the optical imaging lens, and T3 is a thickness of the third lens element along the optical axis.
 10. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: TL/(T1+T5)≤4.100, wherein TL is a distance from the object-side surface of the first lens element to the image-side surface of the sixth lens element along the optical axis, T1 is a thickness of the first lens element along the optical axis, and T5 is a thickness of the fifth lens element along the optical axis.
 11. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: 2.412≤(T5+T6)/T2≤4.758, wherein T2 is a thickness of the second lens element along the optical axis, T5 is a thickness of the fifth lens element along the optical axis, and T6 is a thickness of the sixth lens element along the optical axis.
 12. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: TTL/(T4+G56)≥13.800, wherein TTL is a distance from the object-side surface of the first lens element to an image plane along the optical axis, and T4 is a thickness of the fourth lens element along the optical axis.
 13. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: AAG/G45≤6.000, wherein AAG is a sum of five air gaps from the first lens element to the sixth lens element along the optical axis, and G45 is an air gap from the fourth lens element to the fifth lens element along the optical axis.
 14. The optical imaging lens as claimed in claim 8, wherein the optical imaging lens satisfies: EFL/T5≤4.200, wherein EFL is an effective focal length of the optical imaging lens, and T5 is a thickness of the fifth lens element along the optical axis.
 15. An optical imaging lens, comprising a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element sequentially arranged along an optical axis from an object side to an image side, each of the first lens element to the sixth lens element comprising an object-side surface facing the object side and allowing imaging rays to pass through and an image-side surface facing the image side and allowing the imaging rays to pass through, the six lens elements being the only lens elements having refracting power in the optical imaging lens, wherein a periphery region of the image-side surface of the first lens element is concave; an optical axis region of the object-side surface of the third lens element is concave; a periphery region of the image-side surface of the fourth lens element is concave; an optical axis region of the image-side surface of the sixth lens element is concave; and the optical imaging lens satisfies: (G12+T5)/(G23+G34+G56)≥4.500, wherein G12 is an air gap from the first lens element to the second lens element along the optical axis, T5 is a thickness of the fifth lens element along the optical axis, G23 is an air gap from the second lens element to the third lens element along the optical axis, G34 is an air gap from the third lens element to the fourth lens element along the optical axis, and G56 is an air gap from the fifth lens element to the sixth lens element along the optical axis.
 16. The optical imaging lens as claimed in claim 15, wherein the optical imaging lens satisfies: BFL/T3≥3.100, wherein BFL is a distance from the image-side surface of the sixth lens element to an image plane along the optical axis, and T3 is a thickness of the third lens element along the optical axis.
 17. The optical imaging lens as claimed in claim 15, wherein the optical imaging lens satisfies: TTL/T5≤7.800, wherein TTL is a distance from the object-side surface of the first lens element to an image plane along the optical axis.
 18. The optical imaging lens as claimed in claim 15, wherein the optical imaging lens satisfies: 2.660≤ALT/(T3+T6)≤3.701, wherein ALT is a sum of thicknesses of the first lens element, the second lens element, the third lens element, the fourth lens element, the fifth lens element, and the sixth lens element along the optical axis, T3 is a thickness of the third lens element along the optical axis, and T6 is a thickness of the sixth lens element along the optical axis.
 19. The optical imaging lens as claimed in claim 15, wherein the optical imaging lens satisfies: TL/(T3+T5)≤4.000, wherein TL is a distance from the object-side surface of the first lens element to the image-side surface of the sixth lens element along the optical axis, and T3 is a thickness of the third lens element along the optical axis.
 20. The optical imaging lens as claimed in claim 15, wherein the optical imaging lens satisfies: V3-V6≥20.000, wherein V3 is an Abbe number of the third lens element, and V6 is an Abbe number of the sixth lens element. 